Fastener-driving tools are well known in the art. Such tools can generally be classified into two broad classes of tools, based on their source of driving power. The first class of tools, sometimes referred to as fluid-powered fastener-driving tools, depend on the use of pressurized fluids (e.g., air) to provide their driving power. Such tools are exemplified by the following U.S. Pat. Nos.: 3,952,398, 4,040,554, 4,122,904, 4,196,833 and 4,346,831. The second class of tools, sometimes referred to as powder-actuated fastener-driving tools, depend on the use of explosive cartridges to provide their driving power. Such tools are in turn exemplified by the following U.S. Pat. Nos.: 3,168,744, 3,499,590, 3,552,625, 3,554,425, 3,565,313 and 3,743,159.
Unfortunately, existing powder-actuated fastener-driving tools of the type which are adapted to accept a strip of charges tend to suffer from a number of serious problems. Typically, these tools tend to have a complex construction, so that they are relatively expensive to manufacture, fairly difficult to assemble, and prone to mechanical failure. Second, in many powder-actuated fastener-driving tools, the exhaust passages used to vent the hot gases of combustion from the interiors of the tools are inadequate for the task required; as a result, the tools are relatively noisy, have significant recoil, are energy inefficient, and/or tend to jam often on account of the buildup of spent powder within the tools. Third, none of the existing powder-actuated fastener-driving tools is capable of using a so-called "Red" charge cartridge (also known in the industry as a "Power Level 5" cartridge, or simply a "No. 5" cartridge) with a light-weight fastener (e.g., a 1/2" long nail) and still be considered a "low velocity" tool. In this respect, it is noted that a "low velocity" tool is one which has a maximum velocity of 300 feet per second measured six feet from the muzzle. Another problem with many powder-actuated fastener-driving tools is that they have a construction which does not allow for easy disassembly in the field so as to facilitate maintenance. Another common limitation of prior designs is that they cannot be easily adapted to drive fasteners of differing types and dimensions. Also existing powder-actuated fastener-driving tools are typically not easily adapted to be mounted to a pole assembly or else available pole assemblies for such tools are inconvenient to use or permit accidental firing.
In addition to the aforementioned problems common to many existing tools, at least one tool of that type also utilizes a trigger assembly of relatively great complexity, so that the aforementioned problems of expense of manufacture, difficulty of assembly, and tendency towards mechanical failure are exacerbated. In addition, at least one existing powder-actuated fastener-driving tool utilizes a cam arrangement in its cartridge advance mechanism which tends to wear excessively, so that increased maintenance is required or tool jamming may occur.